In communication systems, messages are transmitted between transmitter and receiver. Radio communication systems are a specific example of communication systems. Here, messages comprising, for example, voice information, image information, video information, SMS (Short Message Service), MMS (Multimedia Messaging Service) or other data, are transmitted with the aid of electromagnetic waves between transmitting and receiving radio station via a radio interface. Depending on the specific embodiment of the radio communication system, the radio stations here can be various types of subscriber-side radio stations or network-side radio devices such as base stations or radio access points. In a mobile radio communication system, at least some of the subscriber-side radio stations are mobile radio stations. The electromagnetic waves are emitted using carrier frequencies which lie in the frequency band provided for the respective system.
Mobile radio communication systems are often configured as cellular systems e.g. in conformance with the GSM (Global System for Mobile Communication) or UMTS (Universal Mobile Telecommunications System) standard, with a network infrastructure including e.g. base stations, devices for monitoring and controlling the base stations and further network-side devices. Apart from these cellular, hierarchical radio networks organized on a wide-area (supralocal) basis, there are also wireless local area networks (WLANS) with a range of radio coverage that is as a rule significantly more limited spatially.
In the transmission of scalable data, the basic information is transmitted and, in addition, information complementing the basic information. Scalable data consequently has the property that it can be available at the receiver with a reduced quality, the receiver decoding only the basic information or the basic information and some the complementing information, and not the basic information and all of the complementing information. Data which is transmitted simultaneously to multiple subscribers can as scalable information be transmitted by the transmitter with the optimum possible quality, i.e. as basic information and complementing information. When the data is distributed in the communication network to the different receivers, the data can be adapted/scaled such that different parts of the complementing data are forwarded to the different receivers, so that only the complementing information needed or requested by the respective receiver is transmitted. Due to the shortage of transmission resources, this proves to be advantageous in radio communication systems in particular. The adaptation/scaling can also be carried out by a terminal device which decides to decode only some of the complementing information.